Hi all - I have some questions regarding four squares - My career was in
commerce and not electronics so please excuse what may seem silly questions.
Tom W8JI advocates that the normal 90/180 phasing is not the optimum - the
117/234 phasing gives more gain whilst making the lobes narrower which means to
get the full effect there needs to be 8 selectable directions instead of 4 - I
wish to follow Tom's suggestions - but I am unsure of the following - is the
size of the 4 square fixed by the frequency or does the different phasing mean
that the sides are of a diffent length?The four quarter wave feed lines I
presume are longer to accomodate the 117 instead of 90 - is that correct? If so
- to get the 234 phase do I put a twice the length of the feeds to each
vertical in series with the front vertical?With the longer feeds to each
antenna will the same current / voltage rules still apply in the same way as if
they were quarter wave feedlines?Sourcing vacuum
relays is a problem - can anyone pass on where in the world I can get 10 DPST
1 4PST and 3 SPST - if I cannot locate vacuum relays and I revert to normal
relays then what current rating should I use - I guess this is allied to the RF
current going into each antenna - assume 400watts as this is the UK max - any
help would be appreciated - regards Dave G3RCQ
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